1. Field of the Invention
The present invention relates to a semiconductor device, a method for manufacturing the same, and a liquid jet apparatus, in particular, to a liquid jet apparatus applicable to a recording apparatus to be used as an output terminal of information equipment such as a copying machine, a facsimile, a word processor, a computer or the like, an apparatus to be used for manufacturing a deoxyribonucleic acid (DNA) chip, an organic transistor, a color filter or the like, and the like, a semiconductor device usable to the liquid jet apparatus suitably, and a method for manufacturing the same.
2. Related Background Art
A description is given to a liquid jet apparatus by illustrating a recording apparatus such as an ink jet printer.
A conventional recording apparatus installs an electro-thermal conversion element and a semiconductor for driving the same (hereinafter referred to as an xe2x80x9celectro-thermal conversion element driving semiconductor devicexe2x80x9d) therein as the recording head thereof.
FIG. 38 is a sectional view showing the section structure of a part of a conventional ink jet recording head. A reference numeral 101 indicates a semiconductor substrate made of a single crystal silicon.
A reference numeral 102 designates an n-type well region; a reference numeral 108 designates a drain region; a reference numeral 115 designates an n-type field relaxation drain region; a reference numeral 107 designates an n-type source region; and a reference numeral 104 designates a gate electrode. These components constitute an electro-thermal conversion element driving semiconductor device 130 using a metal-insulator semiconductor (MIS) type field effect transistor.
Moreover, a reference numeral 117 designates a silicon oxide layer as a thermal storage layer and an insulator layer; a reference numeral 118 designates a tantalum nitride film as a heat resistor layer; a reference numeral 119 designates an aluminum alloy film as wiring; and a reference numeral 120 designates a silicon nitride film as a protective film. All of the components described above constitute a substrate 140 of the recording head.
Hereupon, a reference numeral 150 designates a portion being a heating portion, and a reference numeral 160 designates a portion where ink is jetted. Moreover, a top plate 170 forms a liquid path 180 in association with the substrate 140.
Other electro-thermal conversion element driving semiconductor devices are disclosed in Japanese Patent Application Laid-Open Nos. 5-185594, 6-069497, 10-034898, and the like.
Now, although many improvements have been made in the aforesaid conventionally structured recording head and the aforesaid electro-thermal conversion element driving semiconductor device, recently the following properties of these products have further been required: being capable of being driven in high speed, using less energy, being highly integrated, being manufactured at low costs, and having high properties. In particular, the high density integration of switching devices has been insufficient in conventional head structures. Moreover, it has been easy to happen the rise of a substrate potential (latch up) caused by the lowness of the breakdown voltages of the conventional head structures can easily occur in operation.
Besides, the structures of electro-thermal conversion element driving semiconductor devices have been known which are disclosed in Japanese Patent Application Laid-Open Nos. 62-098764, 5-129597, 8-097410, 9-307110, and the like.
When insulated gate type transistors are used for driving electro-thermal conversion elements, in addition to the improvements of their breakdown voltages, the improvements of the following properties have become required more: being capable of being driven in high speed, using less energy, being highly integrated, being manufactured at low costs, and having high properties. In particular, the uniformity of properties of transistor devices has been insufficient when the transistor devices are integrated in a high density in conventional semiconductor device structures.
A first object of the present invention is to provide a semiconductor device, a method for manufacturing the same, and a liquid jet apparatus that can decrease the occupation areas of switching devices superior in break down resistances on chips to enable the further higher integration of electro-thermal conversion element driving semiconductor devices.
A second object of the present invention is to provide a semiconductor device, a method for manufacturing the same, and a liquid jet apparatus that have low possibilities of the occurrence of disadvantages owing to channeling and have transistors equal in characteristics and further are possible to realize the higher integration of semiconductor devices.
The aforesaid first object of the present invention is achieved by a semiconductor device comprising: a plurality of electro-thermal conversion elements; and a plurality of switching devices for flowing electric currents through the plural electro-thermal conversion elements, wherein: the electro-thermal conversion elements and the switching devices are integrated on a first conductive type semiconductor substrate; the switching devices are insulated gate type field effect transistors that severally include: a second conductive type first semiconductor region formed on one principal surface of the semiconductor substrate; a first conductive type second semiconductor region for supplying a channel region, the second semiconductor region being formed to adjoin the first semiconductor region; a second conductive type source region formed on the surface side of the second semiconductor region; a second conductive type drain region formed on the surface side of the first semiconductor region; and gate electrodes formed on the channel region with a gate insulator film put between them; and the second semiconductor region is formed by a semiconductor having an impurity concentration higher than that of the first semiconductor region, the second semiconductor region being disposed between two of the drain regions arranged side by side so as to separate the drain regions in a traverse direction.
Here, it is preferable that the second semiconductor region is formed adjacently to the semiconductor substrate.
Moreover, the source region and the drain region are preferably disposed alternately in traverse directions.
The electro-thermal conversion elements are preferably connected with the drain region.
Two of the gate electrodes are preferably formed with the source region put between them.
An arrangement direction of the plural electro-thermal conversion elements and an arrangement direction of the plural switching devices are preferably in parallel.
The drain regions of at least two of the insulated gate type field effect transistors are preferably connected with one of the electro-thermal conversion elements, and the source regions of the plural insulated gate type field effect transistors are preferably commonly connected.
The effective channel lengths of the insulated gate type field effect transistors are preferably determined on a difference of transversal diffusion quantities between in the second semiconductor region and in the source region.
The insulated gate type field effect transistors severally preferably comprise a first conductive type diffusion layer for pulling out an electrode such that the diffusion layer penetrates the source region.
Drain sides of the gate electrodes are preferably formed on insulator films thicker than the gate insulator film.
Drain sides of the gate electrodes are preferably formed on field insulator films.
The first semiconductor region is preferably a well formed by introducing a reverse conductive type impurity from a surface of the semiconductor substrate.
The first semiconductor region is preferably composed of a plurality of wells formed by introducing a reverse conductive type impurity from a surface of the semiconductor substrate and by transversal separation at every drain region.
The second semiconductor region preferably includes a lower region and a higher region in which its impurity concentration is higher than that in the lower region.
The drain region is preferably disposed separately from drain side end portions of the gate electrodes.
The source region preferably overlaps the gate electrodes.
The drain sides of the gate electrodes are preferably formed on insulator films thicker than the gate insulator film, and the drain region preferably aligns itself with end portions of the thicker insulator films.
The second semiconductor region, the source region and the drain region preferably have sectional structures symmetrical on its right side and on its left side, the structures being formed by introducing impurities by oblique ion implantation.
The semiconductor substrate is preferably an OFF substrate.
Liquid exhaust portions corresponding to the electro-thermal conversion elements are preferably formed.
Moreover, the first object is achieved by a method for manufacturing a semiconductor device in which a plurality of electro-thermal conversion elements and a plurality of switching devices for flowing electric currents through the plural electro-thermal conversion elements are integrated on a first conductive type semiconductor substrate, the method comprising the steps of: forming a second conductive type semiconductor layer on one principal surface of the first conductive type semiconductor substrate; forming a gate insulator film on the semiconductor layer; forming a gate electrode on the gate insulator film; doping a first conductive type impurity by utilizing the gate electrode as a mask; forming a semiconductor region by diffusing the first conductive type impurity; and forming a second conductive type source region on the surface side of the semiconductor region by utilizing the gate electrode as a mask and a second conductive type drain region on the surface side of the second conductive type semiconductor layer.
Moreover, the first object is achieved by a method for manufacturing a semiconductor device in which a plurality of electro-thermal conversion elements and a plurality of switching devices for flowing electric currents through the plural electro-thermal conversion elements are integrated on a first conductive type semiconductor substrate, the method comprising the steps of: forming a second conductive type semiconductor layer on one principal surface of the first conductive type semiconductor substrate; forming a field insulator film on the semiconductor layer selectively; forming a gate insulator film on the semiconductor layer; forming a gate electrode on the gate insulator film and the field insulator film; doping a first conductive type impurity by utilizing the gate electrode as a mask; forming a semiconductor region by diffusing the first conductive type impurity; and forming a second conductive type source region on the surface side of the semiconductor region by utilizing the gate electrode as a mask and a second conductive type drain region on the surface side of the second conductive type semiconductor layer by utilizing the field insulator film as a mask.
Here, it is preferable for the method to comprise the steps of: performing a first conductive type ion implantation into at least a channel region put between the source region and the semiconductor layer on the surface side of the semiconductor region through the gate electrode after the step of forming the semiconductor region; and performing a heat treatment for activating the implanted impurity electrically.
It is also preferable for the method to comprise the steps of: performing a first conductive type ion implantation into at least a channel region put between the source region and the semiconductor layer on the surface side of the semiconductor region through the gate electrode after the step of forming the semiconductor region; and performing a heat treatment for activating the implanted impurity electrically, wherein the ion implantation is ion implantation in which ions of boron are implanted in energy of 100 keV or more.
At least two of the drain regions of MIS type field effect transistors being switching devices are preferably connected with one of the electro-thermal conversion elements, and the sources of the plural MIS type field effect transistors are preferably commonly connected.
Besides, the aforesaid second object is achieved by a method for manufacturing a semiconductor device, the method comprising the steps of: forming a second conductive type semiconductor layer on one principal surface of the first conductive type semiconductor substrate; forming a gate insulator film on the semiconductor layer; forming a gate electrode on the gate insulator film; doping a first conductive type impurity by utilizing the gate electrode as a mask; forming a semiconductor region by diffusing the first conductive type impurity; and forming a second conductive type source region on the surface side of the semiconductor region by utilizing the gate electrode as a mask and a second conductive type drain region on the surface side of the second conductive type semiconductor layer, wherein the method can obtain a transistor structure symmetrical to the source region.
Here, the step of doping the first conductive type impurity preferably includes a step of performing ion implantation obliquely to the principal surface of the semiconductor substrate while rotating the semiconductor substrate.
The step of forming the second conductive type source region preferably includes a step of performing ion implantation obliquely to the principal surface of the semiconductor substrate while rotating the semiconductor substrate.
The step of forming the second conductive type drain region preferably includes a step of performing ion implantation obliquely to the principal surface of the semiconductor substrate while rotating the semiconductor substrate.
The step of doping the first conductive type impurity preferably includes a step of performing ion implantation into the principal surface of an OFF substrate being the semiconductor substrate in a normal line direction of the principal surface.
The step of forming the second conductive type source region preferably includes a step of performing ion implantation into the principal surface of an OFF substrate being the semiconductor substrate in a normal line direction of the principal surface.
The step of forming the second conductive type drain region preferably includes a step of performing ion implantation into the principal surface of an OFF substrate being the semiconductor substrate in a normal line direction of the principal surface.
The step of doping the first conductive type impurity preferably includes a step of performing ion implantation of boron in high energy of 100 keV or more.
The present invention is a method for manufacturing a semiconductor device in which a plurality of insulated gate type field effect transistors are arranged in an array, the method comprising the steps of: forming a second conductive type first semiconductor region on one principal surface of a first conductive type semiconductor substrate; forming a gate insulator film on the first semiconductor region; forming a plurality of gate electrodes on the gate insulator film; forming a first conductive type second semiconductor region by diffusing a first conductive type impurity after implanting the impurity between adjoining two of the gate electrodes by using the two gate electrodes as masks at a fixed angle to a normal line direction of the semiconductor substrate while rotating the semiconductor substrate; and forming a second conductive type source region in the second semiconductor region by utilizing the two gate electrodes as masks and a second conductive type drain region severally in two of the first semiconductor regions disposed to put the second semiconductor region between them by implanting the impurity at the fixed angle to the normal line direction of the semiconductor substrate while rotating the semiconductor substrate.
The present invention is a method for manufacturing a semiconductor device in which a plurality of insulated gate type field effect transistors are arranged in an array, the method comprising the steps of: forming a second conductive type first semiconductor region on one principal surface of a first conductive type semiconductor substrate; forming a field insulator film selectively on the first semiconductor region; forming a gate insulator film on the first semiconductor region; forming gate electrodes on the gate insulator film and the field insulator film; forming a first conductive type second semiconductor region by diffusing a first conductive type impurity after implanting the impurity between two of the gate electrodes by using the two gate electrodes as masks at a fixed angle to a normal line direction of the semiconductor substrate while rotating the semiconductor substrate; and forming a second conductive type source region in the second semiconductor region by utilizing the two gate electrodes as masks and a second conductive type drain region severally in two of the first semiconductor regions disposed to put the second semiconductor region between them by utilizing the field insulator film as a mask by implanting the impurity at the fixed angle to the normal line direction of the semiconductor substrate while rotating the semiconductor substrate.
Here, the second semiconductor region is preferably formed deeper than the first semiconductor region.
A heating resistance element connected with the drain region electrically is preferably formed.
The present invention is a method for manufacturing a semiconductor device, the method comprising the steps of: forming a second conductive type first semiconductor region on a first conductive type semiconductor substrate including one principal surface having a plane direction inclining against a lower dimensional plane direction; forming a gate insulator film in the first semiconductor region; forming a gate electrode on the gate insulator film; forming a second semiconductor region by diffusing a first conductive type impurity after performing ion implantation of the impurity into the semiconductor substrate perpendicularly by utilizing the gate electrode as a mask; and forming a second conductive type source region in the second semiconductor region by utilizing the gate electrode as a mask and a second conductive type drain region in the second semiconductor region by performing ion implantation of impurities severally perpendicularly to the semiconductor substrate.
The present invention is a method for manufacturing a semiconductor device, the method comprising the steps of: forming a second conductive type first semiconductor layer on a first conductive type semiconductor substrate including one principal surface having a plane direction inclining against a lower dimensional plane direction; forming a field insulator film in the first semiconductor region selectively; forming a gate insulator film in the first semiconductor region; forming a gate electrode on the gate insulator film and the field insulator film; forming a second semiconductor region by diffusing a first conductive type impurity after performing ion implantation of the impurity into the semiconductor substrate perpendicularly by utilizing the gate electrode as a mask; and forming a second conductive type source region in the second semiconductor region by utilizing the gate electrode as a mask and a second conductive type drain region in the second conductive type second semiconductor region by utilizing the field insulator film as a mask by performing ion implantation of impurities severally perpendicularly to the semiconductor substrate.
Here, the plane direction of the principal surface of the semiconductor substrate preferably inclines to the lower dimensional plane direction at a degree of a range from 3xc2x0 to 10xc2x0.
Moreover, the plane direction of the principal surface of the semiconductor substrate preferably inclines to a (100) plane at a degree of a range from 3xc2x0 to 10xc2x0.
The plane direction of the principal surface of the semiconductor substrate preferably inclines to a (100) plane at an angle of 4xc2x0.
The step of forming the second semiconductor region preferably diffuses the first conductive type impurity such that the impurity is deeper than the first semiconductor region.
A plurality of insulated gate type field effect transistors are preferably arranged in an array.
The present invention is a semiconductor device in which a plurality of insulated gate type field effect transistors are disposed in an array, the insulated gate type field effect transistors severally comprising: a second conductive type first semiconductor region formed on a first conductive type semiconductor substrate including one principal surface having a plane direction inclining to a lower dimensional plane direction; a first conductive type second semiconductor region formed to separate the first semiconductor region, the second semiconductor region having a concentration higher than that of the first semiconductor region; a second conductive type source region formed in the second semiconductor region; and a second conductive type drain region formed in the first semiconductor region.
Here, the plane direction of the principal surface of the semiconductor substrate preferably inclines to the lower dimensional plane direction at a degree of a range from 3xc2x0 to 10xc2x0.
Moreover, the plane direction of the principal surface of the semiconductor substrate preferably inclines to a (100) plane at a degree of a range from 3xc2x0 to 10xc2x0.
Furthermore, the plane direction of the principal surface of the semiconductor substrate preferably inclines to a (100) plane at an angle of 4xc2x0.
The depth of the second semiconductor region is preferably deeper than that of the first semiconductor region.
A liquid jet apparatus according to the present invention comprises: the aforementioned semiconductor device including liquid exhaust portions corresponding to electro-thermal conversion elements, a liquid container for containing liquid jetted from the liquid exhaust portions by means of the electro-thermal conversion elements; and a controller for supplying a drive controlling signal for driving insulated gate type field effect transistors in the semiconductor device.
According to the present invention, because a drain concentration can be set to be lower than a channel concentration and the drain can be formed to be sufficiently deep, a semiconductor device has a high breakdown voltage that makes it possible to flow a large amount of electric currents, and the semiconductor device has a low on-resistance that makes it possible to operate at a higher speed, and further the semiconductor device can realize the high integration thereof and the saving of its consumption energy. Then, according to the aforesaid configurations of the present invention, even in a case of a semiconductor device requiring an array configuration compose of a plurality of transistors, electrical isolation between devices can be performed without increasing costs.
Moreover, according to the present invention, a transistor array having even characteristics and being highly integrated can be provided. In particular, when double-diffused MOS FET""s (DMOS transistors) are used as switching devices, leakage currents flowing from drains to the substrate can be suppressed and the concentration of an electric field can be suppressed, and thereby the breakdown voltage can be improved.